Gardeners Corner Global Energy Policy

So it's back to the old carpet sweepers that were pushed and pulled and put down just as much dirt as they picked up.

 

Just compulsory purchase then and re house the populace on a Nice
Scottish Island of Gruinard
Plenty of water and free space, not over populated


Jack McHammocklashing

 

Plenty of other countries have pipelines to move water to dry areas, particularly Australia. I remember seeing their huge pipeslines when visiting Adelaide some years ago. I think they took water from the Murray River to various locations. Don't see why it shouldn't work here.

 

No Jack, leave them there and I'll have the Scottish island, preferably uninhabited apart from wildlife! :yess:

 

Yup, I'm not doubting it would work, but its an obscene use of energy IMO.

Although ... solar power pumps could raise the water - it doesn't matter when that happens, provided you can store it at the raised height, and then allow gravity to "deliver" it. Might even be able to generate electricity on the down-slope - so only "deliver" it when there is also a need for instant electricity generation (i.e. the sort of circumstances that water-pumped-up-hill is currently used to generate electricity for). Solar powered pumps are also going to be doing more work ('coz more sun ) in Summer, when the extra water will be required.

Still think its an obscene use of energy, even if only the embedded energy in the pipes, pumps and infrastructure of the whole project.

 

Oh no you would not Sheal

It is





ANTHRAX ISLAND



Jack McH

 

I picked some data at random:

New York water system provides 4,500,000 m3 per day of drinking water to 9,000,000 consumers (dunno if that includes Business / Factory use or not)

(The same Wikipedia article says that "The New York City water supply system leaks at a rate of up to 140,000 m3 per day", dunno if that is included either.)

Anyways, at face value, averaged out, that's 500 litres per person per day. I guess it does include business use, irrigation and leaks then 'coz I sure couldn't drink half a tonne of water a day!

So if we are going to pump water we are going to need to move half a tonne per person per day (give or take an order or two of magnitude ...). I just don't think that is right, sane, or affordable.

 

Perhaps I'll stay on the one I'm on then for a while.

 

Don't discount the use of Hydraulic Rams, they run for nothing once built.

 

Good point. I saw something on tomorrows world many years ago, I wonder if it has ever seen the light of day?

A reel of pipe (like the thing that you store garden hose on) with the spindle horizontal and in line with the flow of the river. Some fins / propeller added to make the reel of pipe turn using the flow of the river. As the pipe's open end went into the river it picked up some water, and likewise when it turned through the air, and this moved the "slugs" of water along the coil of pipe (like an Archimedes screw). From memory the Head that it could lift was quite respectable (and it didn't all pour out of the sides like an Archimedes screw!)

Why don't we do this for hydro electric power then? Plenty of places that have a "lake" for storage, at some altitude, and use surplus electricity to pump the water up-hill, and then generate electricity, on demand, by releasing the water down the hill. (70% efficient I think)

Instead of having socking great dams for Hydro just use a Ram to pump the stuff up hill, to a smaller lake that doesn't have to be in the valley of the river itself, and can probably be somewhere that is not prime alluvial agricultural land either, nor displaces millions of people ...

If you are building a reservoir for drinking water storage that's different, but I still think its a bad idea - get it out of a hole in the ground (and if you need to "flow" the river into the bedrock somewhere else to refuel it)

But these things would have been done already if they were practical, so I doubt this is a brand-new and viable idea.

 

I had an idea. I'm sure wind farms have been mentioned, as has hydrogen gathered by electrolysis.

Wind power has a big flaw. The wind has to be just right. If the turbines turn too slowly, they can't match the phase of the grid. Turn too fast and the bust. The latter is controlled by fairly conventional brakes, and just like the brakes on our cars, they work by throwing energy away through heat and friction.

Hydrogen is hard to store and pipe, and plus it takes more energy to extract it by electrolysis than you get back by burning it.

So how about this then. Electrolysis isn't too fussy about things like voltage, frequency, phase etc. As long as a current flows through the water from one electrode to the other, then hydrogen and oxygen will come out in the perfect ratio for an efficient burn. So here's the trick. For every offshore wind farm, you have a comparatively small electrolysis plant in the sea, at the site. On top of the electrolysis plant is a storage tank for the gas, just to act as a buffer, and at the end of that you have a gas powered turbine to generate electricity.

So lets say the wind is giving rock all. Its getting to the point where the brakes need to be applied on the wind turbines to prevent them from tearing themselves apart. Another way brake, is to apply close to short circuit to the turbines (an inescapable law of physics is that 1 horse power = 712 watts - so the more current you draw from an alternator, the greater the physical resistance, ie braking will be). So on the rare occasions when the wind turbines are generating a surplus, instead of wasting that with old fashioned friction brakes, you divert that surplus to the electrolysis plant, and the resulting gas is stored in the buffer tank.

Then the wind drops, a lot. Now there is not enough wind to make the wind turbines generate power that can go to the grid. Our stored gas on top of the electrolysis plant then powers a turbine to generate power. Just as the modern car engine is controlled very precisely with electronics, so could our hydrogen powered generator. Meanwhile, there is still enough wind to turn the wind turbines, but not fast enough to match the phase of the grid. Doesn't matter, that energy that would normally be wasted goes to our electrolysis machine generating gas, albeit at a lower rate, for our hydrogen fuelled generator. Of course at some point, the buffered gas would run out (in prolonged periods of very calm weather) but instead of about half the available wind energy being wasted, you end up wasting maybe 10%. No network of pipes for the hydrogen or anything clever. Just like using hydrogen from electrolysis as a slice of bread to mop up the gravy so to speak.

 

The like button isn't good enough for that one, love it

This will form part of the GC Manefesto when we seize control from the failing system of Government in the EU.

:grouphug:

 

Clueless its brilliant. However I don't think having a Turbine on each Windflower will be cost effective. Could the gas drive the same generator that the blades turn? (attach a turbine of some sort to the generator that the blades would normally turn).Either disconnect the blades (by clutch) or have some sort of gearbox so that what little assistance the wind is providing is combined with the burning of the gas.

 

I was thinking just one gas turbine for the entire site. So if you have 100 wind turbines in the farm, you'd still just have one separate gas installation. Nice and cheap and simple, and requiring no change to the design of the wind turbines.

There are a couple of technical issues to overcome, but I think the engineers could easily enough crack it. One that springs to mind is that the water inside the electrolysis chamber would have to be completely isolated electrically from the rest of the sea, otherwise you'd have a lot of dead sea creatures having been electrocuted, and a significant amount of the gas would simply escape. Stuff like that could be overcome easily enough. In that one example, you just a valve that lets sea water into the sealed chamber once the water level drops too low, then closes. The power comes on, electrolysis begins, and there's absolutely no need to pump anything because the electrolysis process itself would build up plenty of pressure.

 

So you are burning the Hydrogen and the Oxygen together? (I'm having a probably dumb thought about why I've never seen H + Ox2 in a single tank as a fuel, presumably you'd get some energy from burning the Oxygen. Maybe Hydrogen in tanks is not made by electrolysis, or Hospitals [or some other industry] take all the Oxygen tanks they can fill)

You could just use a fuel cell and the Hydrogen on its own (no Turbine needed then?)

Dunno how the efficiencies compare.